CET (Custo Efetivo Total) is a standardized annual rate that must be disclosed by all Brazilian banks for credit operations, as required by CMN Resolution 3.517/2007. It allows consumers to compare different loan offers on equal footing.
Effective Annual Rate Calculator (CET)
Calculate the true cost of a loan beyond the nominal interest rate.
What CET is and why it matters more than the nominal interest rate.
The CET (Custo Efetivo Total — Total Effective Cost) is an annual rate that encapsulates all loan costs: nominal interest, admin fees, insurance, IOF and other charges. Required by Banco Central Resolution CMN 3.517/2007, it is the most honest measure of a credit product's real cost. This tool calculates the CET using the Newton-Raphson method to find the internal rate of return of the cash flow.
Enter the loan details to see the effective annual rate.
- Enter the loan amount, monthly installment and number of installments.
- Add any admin fees charged upfront and monthly insurance if applicable.
- Compare the CET against the nominal rate — the difference shows hidden costs.
Sources and references for this tool
These references help contextualize formulas, standards, APIs and limitations used on this page. They do not replace professional validation when a result has legal, financial, medical or operational impact.